1. Technical Field
This invention relates generally to conveyors and conveyor systems, and more particularly to an extendible conveyor apparatus with rollers arranged in an adjustable-length bed suitable for any of various conveyor applications.
2. Description of Related Art
Some conveyor applications require a conveyor that the user can adjust in overall length. The user can lengthen or shorten the conveyor to suit operating needs. A typical existing gravity conveyor, for example, might include multiple fixed-length, skate wheel conveyor sections in overlapping relationship. The amount of overlap is adjusted to achieve the desired overall length. An existing form of belt conveyor, might include multiple fixed-length belt conveyor sections and belt-to-belt transfer plates. Yet another existing form of conveyor might include spaced-apart rollers mounted between extendible side rails having crisscrossed members that enable a user to extend them something like a scissors boom.
Although effective in many respects, existing conveyors often have certain problems that make them unsuited for many extendible conveyor applications. Gravity conveyors rely on gravity to move the parcels or other objects being conveyed. They don't work when level or inclined upwardly. In addition, overlapping gravity conveyor sections result in abrupt vertical steps between overlapping sections that may be unacceptable. Multiple-belt conveyors involve weight, noise, and complicated construction, and extendible conveyors with scissor-boom-like side rails cause roller spacing to change when moved between retracted and extended positions. For these and other reasons that will become more apparent from the following description, users need a better extendible conveyor.